Amend2 Magazine, 223 Remington/556NATO, 20 Rounds, Fits AR Rifles, Polymer, Black AM10556MOD2BLK20 The Amend2 20-round magazine is a sturdy" reliable AR15/M4/M16 magazine made of advanced polymer material. It is light" durable and an excellent alternative to the standard M4/M16 USGI aluminum magazines. The 20 round body profile is ideal for added maneuverability and weapon handling.